The Party Crashers
by Sea and Chaos
Summary: Magnus was having a great day, throwing a party for Chairman Meow and getting Alec to bring along the shadowhunters. Then, a knock interrupted the party and now there is a group of demigods sitting in front of Magnus and the Nephilim.


**AN: Yo! Told you all there might be a one-shot. Now, if this gets enough likes and such, I might consider continuing it after I finish one of my other stories. For now, it is a one-shot. I can't remember the name, but there was a challenge in this section that really peaked my interest and I asked to do it in my spare time. Here is the result of me doing it, forgetting it happened, and then finding it and rereading it. I hope you all like it!**

 **I am merely playing in this large sandbox, it just belongs in the neighbor's yard.**

 **Giada Draven, out!**

Magnus was having a splendid day. After all, he was throwing another one of his parties, this time because Chairman Meow had come back after a long stint of about five days. Of course, not that he needed an excuse for a party, downworlders didn't care the reason. He had finally gotten his boyfriend, Alec, to agree to come and bring the other shadowhunters with him. So, he was very disgruntled when he found the doorbell being rang, after all of the guests had arrived.

Going to answer it, he was surprised when a group of eight people stood there. Magnus arched an eyebrow at them, his little ability still annoying Clary because she couldn't arch only one no matter how she tried. "And who are you, especially the little cutie who's hiding in the shadows?" Of course, he knew who they were, having travelled with each of them. Because, though it didn't seem it, Percy Jackson would hide this world from his friends to protect them and himself, to save himself the heartbreak. But they didn't know who he truly was, so he had to pretend.

As Nico began to blush and stammer, Alec came up behind him and slung his rune covered arm around the warlock. "Please don't go flirting with the kid, Magnus. From his looks he could be a vampire, and I know you don't get along with them so much."

Magnus sighed dramatically, blinking his cat eyes at his unknowing friends. "You know I can't resist, Alec. Besides, he is just so cute." Laughing slightly as Alec mumbled under his breath about how he couldn't help but flirt with _everything_ , Magnus turned back to the demigods. "So, what do you need with the High Warlock of Brooklyn?"

Annabeth blinked at the title, but ignored it in favor of stating their business. "We need help finding our friend; he went missing right before our planned diner. When we talked to his mom, she said that he was off doing something, most likely at a party in Brooklyn. This was the only party that we found when we got here, so we were hoping that he would be here. Have you seen him?"

Shaking his head, he knew he was utterly screwed when Nico stepped out of the shadows, and Annabeth narrowed her eyes. Sighing, he looked back at the mostly drunk partygoers and shouted, "Everyone, out! I gotta take care of some stuff! Thank you for coming together to celebrate the return of Chairman Meow, but you need to go now!" A collective groan was heard as the downworlders left. He saw that the shadowhunters were following, but shook his head at them. He needed people to be here, otherwise who knew what the demigods would do to him.

As soon as the downworlders had left, Magnus snapped his fingers, summoning a bunch of cushions for the group to sit on. Of course, Magnus and Alec claimed a love seat, and Clary, Jace and Simon took a couch. Izzy sat in a lone seat, nursing one of the drinks she had gotten before the bartender left. The newcomers sat on the cushions, not at all caring that it was very undignified.

"So," said Jason, becoming the leader. "Why is it that you lied? Somehow you know who we were talking about without us saying a name, and you were trying to hide him from us. Where is Percy? He didn't leave with everyone else, but he isn't sitting here now." Hazel nodded, looking at him closely to try and find a hint as to where her friend could be.

Magnus sighed, looked at the shadowhunters, then reached into his pocket. Pulling his hand back out, a pack of coloured contacts sat in his palm. Putting them on, the demigods gasped as Alec hugged his boyfriend to his side. There sat an older Percy Jackson, covered in glitter and wearing very well done makeup. His sea green eyes swirled, controlled by his magic so that the hidden cat eyes could not be seen.

Annabeth stood from her place on the floor, walked toward him, and before he could say a word, slapped him. Then she got started, "Perseus Jackson, what are you doing here?! You disappear, and your mom says you're at a party, and when we get here to find you, to make sure that you haven't been kidnapped AGAIN, you try to hide from us! And since when do you have a boyfriend?" By now she was seething, because even though he had never returned her feelings, they had remained best friends. So, she expected to be told everything. She was really mad that she wasn't told about the whole thing.

Wincing slightly, Magnus began to explain, to everyone. "Well, I couldn't exactly tell you that I'm nearly 600 years old. My mother was impregnated by a demon, Asmodeus. She did not know, and had an affair with Poseidon. Before you ask, yes demons are real, and yes, the Greek gods are too. In fact the Romans, the Norse, and the Egyptian are from who I've met." The entirety of the room was surprised, since the existence of the other mythologies had been kept secret.

Clary raised her hand, clearly wanting to ask a question. At his nod, she asked, "What does the affair with a god have to do with anything?"

Magnus nodded. "Smart question. Somehow, his DNA got into the mix, and I am part warlock and part demigod. About 18 years ago, I did an experiment that led to me being able to change into the form of a kid. I figured I might as well go to Camp Half-Blood, so one of the other warlocks in New York let me stay with her, and she pretty much became my mom while I was in my younger form. Went to camp, became friends with you guys, and you know what has happened since. During the year, though, I only went to a school if I needed a cover up. There was a big war, and now we are here."

It was silent for several minutes, the demigods processing that their friend had been through more than they could imagine; the shadowhunters, except Alec, realizing that the warlock had an entirely separate life. After nearly ten minutes, Jace finally spoke. "So, son of the god of the sea? Does that mean you have some _water_ powers?" He raised his eyebrows, laughing to himself until Alec leaned over and punched him in the arm. "Oww!"


End file.
